公开(公告)号：JPH10303997A

公开(公告)日：1998-11-13

申请号：JP7220198

申请日：1998-03-20

Applicant: LUCENT TECHNOLOGIES INC

Inventor： HABBAB ISAM M I ,  SANJAI CASTORIA

IPC: H04L27/22 ,  H04L7/04 ,  H04L27/00 ,  H04L27/233

Abstract: PROBLEM TO BE SOLVED: To compensate the frequency offset of a received signal which has a dot series. SOLUTION: A frequency offset compensator 100 consists of a rotator 104, a dot detector 110, a phase tracer 108, and a switch 106. The rotator 104 receives an angle of rotation and rotates a rail parallel component and a rail vertical component of a receive signal to generate a rotated parallel rail component and a rotated vertical rail component. The dot detector 110 detects a dot series appearing by using the rotated vertical rail component. The phase tracer 108 generates the angle of rotation by using the rotated parallel rail component. The switch 106 is controlled by the dot detector 110 and makes the transmission of the angle of rotation to the rotator 104 effective or ineffective according to whether or not the dot series is present. For example, the dot detector 110 detects the dot series appearing by comparing a value based upon the rotated vertical rail component with a threshold value.

公开(公告)号：CA2228919A1

公开(公告)日：1998-09-27

申请号：CA2228919

申请日：1998-02-05

Applicant: LUCENT TECHNOLOGIES INC

Inventor： HABBAB ISAM M I ,  KASTURIA SANJAY

IPC: H04L27/22 ,  H04L7/04 ,  H04L27/00 ,  H04L27/233 ,  H04M1/00

Abstract: The along and perpendicular rails of a received signal (e.g., modulated usin g multi-phase shift keying) are rotated to compensate for frequency offsets be tween the carrier frequency of the received signal and the reference frequency of the local os cillator. The rotation angles are updated, based on the rotated along rail, during dotting sequence s in the received signal. In one implementation, the dotting sequences are detected based on t he rotate perpendicular rail. The beginnings of dotting sequences are detected by thre sholding the average on the perpendicular rail and the ends of dotting sequences are detected by analyzing the encoded data for non-dotting-sequence values. In a cordless phone application, diffe rent dotting sequences may be used to distinguish base-to-handset transmissions from hand set-to-base transmissions.

公开(公告)号：CA2228919C

公开(公告)日：2001-11-27

申请号：CA2228919

申请日：1998-02-05

Applicant: LUCENT TECHNOLOGIES INC

Inventor： KASTURIA SANJAY ,  HABBAB ISAM M I

IPC: H04L27/22 ,  H04L7/04 ,  H04L27/00 ,  H04L27/233 ,  H04M1/00

Abstract: The along and perpendicular rails of a received signal (e.g., modulated usin g multi-phase shift keying) are rotated to compensate for frequency offsets be tween the carrier frequency of the received signal and the reference frequency of the local os cillator. The rotation angles are updated, based on the rotated along rail, during dotting sequence s in the received signal. In one implementation, the dotting sequences are detected based on t he rotate perpendicular rail. The beginnings of dotting sequences are detected by thre sholding the average on the perpendicular rail and the ends of dotting sequences are detected by analyzing the encoded data for non-dotting-sequence values. In a cordless phone application, diffe rent dotting sequences may be used to distinguish base-to-handset transmissions from hand set-to-base transmissions.